Effects of lead intoxication on the brain uptake of calcium in 30 day old albino rabbits were studied by using Oldendorf technique (Brain Res. 24: 372-376, 1970) which allows for rapidly assessing the passages of solutes across the blood-brain barrier during a single circulating pass. A brain uptake index (BUI) for control gray matter was 0.98 plus or minus 0.06 (SEM) percent and 0.72 plus or minus 0.04 percent for lead poisoned animals (p less than 0.01); for deep white matter the values were 1.45 plus or minus 0.10 (SEM) percent and 1.37 plus or minus 0.09 percent for controls and experimentals (NS). Brain lead content was found to be 0.35 microgram and 0.377 plus or minus 0.10 microgram for controls and lead intoxicated groups. Effects of lead intoxication on 45 Ca release by isolated neural tissue in 30 day old rabbit have shown that pretreatment with lead carbonate (165 microgram for 5 days) inhibits the release of calcium from brain slices. BIBLIOGRAPHIC REFERENCES: O'Tuama LA: Lead toxicity and effects on blood-brain and CNS tranport. In Research to Practice in Mental Retardation. Proc of the 4th Congr of the Intl Ass for the Scientific Study of Mental Retardation, vol. 3, Biomedical Aspects, in press, 1977. O'Tuama LA, Kim CS, Mann JD, Gatzy JT: Increased permeability of periventricular tissues in lead poisoning, in press, Proc. Soc Neuroscience, 1977.